Magnet switch for a transport system

ABSTRACT

Switch (1) of a transport system for a movable transport element (T), where the switch (1) comprises a main track (3) and a secondary track (4) branching off, where the movable transport element (T) can be guided from a transition region (2), in which the secondary track (4) branches off from the main track (3), optionally along the main track (3) or transferred into the secondary track (4), where one or more linear motor sections (5a, 5b, 5c, 5d) are respectively provided at the main track (3) and at the secondary track (4) for moving the movable transport element (T), where a switching force can be generated by way of the one or more linear motor sections (5a, 5b, 5c, 5d) with which the movable transport element (T) can be guided along the main track (3) or transferred into the secondary track (4), characterized in that devices for creasing the switching force are provided in the transition region (2). Transport system comprising such a switch and transport element for such a transport system.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a 371 National Stage of International ApplicationNo. PCT/EP2018/061248, filed May 3, 2018, which claims priority toGerman Patent Application No. 102017208455.3, filed May 18, 2017, thedisclosures of which are herein incorporated by reference in theirentirety.

BACKGROUND

The invention relates to a magnet switch, hereinafter referred to onlyas a switch, for a transport system in which one or more movabletransport element/s with a magnetic reaction element, also referred toas a mover, is/are movable along a transport track by way of one or morelinear motor sections (also referred to as stators). The invention alsorelates to a transport system comprising such a switch and optionallyone, two, or several movable transport elements, as well as a transportelement that is configured for use on such a switch. The transportsystem can be configured in particular for use in the beverage industry,e.g, in a beverage filling system.

Such transport systems with a linear motor drive are known from priorart. For example, DE 10 2013 218389 A1 shows a device and a method forswitching a passive switch for transport systems with linear motors.

In the transport systems, a defined advancing force can be applied toeach individual movable element along a transport track by theinteraction of magnetic fields generated at one or more linear motorsections and a magnetic reaction element that is attached to the movabletransport element. The magnetic reaction elements on the movabletransport elements can consist of permanent magnets and/or non-switchingelectromagnets, or comprise them. A non switching electromagnet istypically an electromagnet connected to a power supply and/or to acontrol unit of the transport device in such a way that preferablycontrollable electrical current passes therethrough, always in the samedirection. The systems can be modular, i.e. can be assembled fromprefabricated modules. The modules can comprise straight and curvedtracks and, in particular, switches.

It is also known to use a normal force (magnetic normal force) suchwhich is a retaining force of the movable transport elementsrespectively in the direction of the adjacent linear motor section (orthe adjacent linear motor sections), to guide the movable transportelements on the transport track. The minimum achievable distance betweenthe movable transport elements and the linear motor sections as yell asa displacement transverse to the axis of motion can be limited and/orguiding the movable transport element on the transport track can bedefined by way of mechanical components (hereinafter also referred to asa guide or a guide curve).

When using two oppositely disposed stators in the transition region, inthat the secondary track branches off form the main track, magneticswitches can be created in which the magnetic normal forces on bothsides are lifted, so that there is no preferred direction. Typically,the magnetic reaction element engages between the two linear motorsections.

By selectively energizing the linear motor sections on both sides of themovable transport elements, the forces in the transition region can nowbe influenced. In particular, the resulting force can be increased onthe desired switch side and the switch can thus be switched such thatthe movable transport element is directed in the desired direction. Theforce for selectively guiding the movable transport element along themain track or in the direction of the secondary track, there by way ofexample by selectively energizing the linear motor sections in thetransition region of the switch, is referred to as the switching force.

Such transport systems are also referred to as long stator linear motorsand are known, for example, from WO 2015 013824 A1.

The normal force (magnetic normal force) in this application means aforce which forms due to the magnetic reaction element at the movabletransport element between the latter and the linear motor sections,where in particular the normal force can typically also be present dueto the magnetic reaction element without applying current to the linearmotor sections.

It can be based, for example, on the reluctance force between themagnetic reaction element on the movable transport element and the corein the stator, typically an iron core. It can serve, in particular, tostabilize or retain the movable transport elements during transportrelative to the stators, in particular to retain them on a guide. inaddition to the normal forces, switching forces are now also employed inthe switch region which are based on an interaction between the magneticfields of the movable transport element and the stator(s). Theseswitching forces are superimposed onto the normal force.

Additional forces can arise due to tolerances from production or ariseduring operation with respect to the distances between movable transportelements and stators, and due to magnetic strength of electromagnetspossibly employed in the movable transport elements. Such tolerances cancause the normal forces to be greater in the direction of one statorthan the normal forces of the stator arranged on the other side, so thatthis can lead to malfunctions.

SUMMARY

The invention comprises a switch of a transport system for a movabletransport element according to claim 1, a transport element as well as atransport system comprising such a switch. Advantageous embodiments aredescribed in the dependent claims. The transport system can be designed,in particular, for use in the beverage industry, e.g. in a beveragefilling system.

According to the invention,the relationship of the normal force to theswitching forces in the switch region should be selected such that theswitch functions reliably. Since the disturbances are typically greaterthe greater the normal force, optimization of the relationship betweenthe normal force to e switching force typically also changes therelationship of disturbances to the switching force.

In a switch according to the invention, the normal force and/or theswitching force in the transition region of the switch can therefore beselected in such a way that the switch functions reliably.

In the region of the switch, in particular the transition region inwhich the secondary track branches off the main track, the transportsystem is typically configured in such a way that the guiding effect ofthe normal force is irrelevant, i.e. in particular reduction of thenormal force does not harm the system. This can be done, for example, bya guide, e.g. on the stators. Such a guide can be present, for example,only in the region of a switch, only in the transition region of aswitch, or optionally also in other or all regions of the transportsystem.

According to the invention, the switch of a transport system for amovable transport element comprises a main track as well as a secondarytrack branching off, where the movable transport element is optionallyguided from a transition region, in which the secondary track branchesoff from the main track, along the main track or transferred into thesecondary track. The direction of motion of the transport element issuch that it moves along the main track in the direction of thetransition region such that it can optionally be guided further alongthe main track or transferred into the secondary track and then, afterpassing through the switch, be moved on either further along the maintrack or along the secondary track (hereinafter also referred to as:direction of motion towards the switch). When “upstream” or “downstream”is used hereafter, then this direction of motion is assumed. Of course,the movable transport element can also be transported from the secondarytrack to the main track or along the main track if it is moved in theopposite direction. However, since no selection of the track must bemade on which the movable transport element is guided, the switching,according to which a movable transport element is guided from one of thetwo secondary tracks to the main track of the switch, shall not befurther dealt with hereafter. A switching force with which the movabletransport element can be either guided on the main track or transferredto the secondary track can typically be generated by the linear motorsections.

According to the invention, devices for changing the normal force can beprovided in the transition region.

The transition region can, in particular, comprise the region or be theregion between the point of the transport track at which a second linearmotor section is added adjacent to the transport element, if thetransport element to other regions is only driven by one linear motorsection, and the point of the transport track at which the transportelement is driven only by the linear motor section of the main track orthe linear motor section of the secondary track and/or (substantially)only affected thereby.

If the transport element in the transport system is moved by two linearmotor sections, then the transition region can alternatively comprisethe region or be the region in which the two linear motor sections nextto the main track are no longer guided parallel to each other (diverge)and where the linear motor sections arranged next to the secondarytracks do not yet run parallel to each other. In such a case, typicallytwo linear motor sections in fact engage at the switch tip, so that thetransport element can again be moved also in the secondary tracks by twolinear motor sections. The beginning of the transition region can bereferred to as that part of the transition region which is passedthrough by a transport element first when it is guided toward the switchin the direction of motion on the main track, i.e. the region at whichthe two linear motor sections next to the main track begin to diverge(or would begin to diverge if they were guided parallel to the edge ofthe transport track).

The transition region can comprise a region in which one (each)transport element takes the same path, regardless of whether it is thenguided further along the main track or into the secondary track. In thisregion, two linear motor sections can optionally be guided parallel toeach other next to the main track (or be arranged in such a way thatthey would be guided in parallel if they were guided parallel to theedge of the transport track). If this region is comprised by thetransition region, devices for increasing the switching force and/or forchanging or reducing the normal force can already be provided in thispart of the transition region. A force effect on the transport elementwhich causes reliable guidance in the desired direction can be ensuredeven upstream of the separation of the paths, either along the maintrack or into the secondary track.

In particular, the devices for changing the normal force can beprovided, for example, in this transition region of the switch. Theprovision of “devices in the transition region of the switch” cancomprise, in particular, that those devices are provided in (at least)part of the transition region of the switch or in the entire transitionregion of the switch.

When giving relative statements in this text, in particular changing,reducing and increasing the normal force (or field strength, number ofturns, etc.), then this statement is given in comparison to anotherregion of the switch, e.g. a region outside the transition region of theswitch, and/or any other region of the switch or transport system. Inparticular, the relative statements can be given, for example, incomparison to the corresponding force or magnitude between a movabletransport element and the linear motor section in the transition regionof the switch and the transport element and the corresponding linearmotor section that is downstream, e.g. downstream at the end of theswitch, and/or upstream.

In the case of a transition region, in particular, a transition regioncomprising a region in which the linear motor sections are guidedparallel to each other next to the main track, the devices forincreasing the switching force and/or for changing or reducing thenormal force in the transition region are typically formed in such a waythat they can change the respective force, e.g. the normal or theswitching force, in comparison to the forces between the respectivetransport element and the linear motor section downstream of thetransition region and/or in comparison to the normal or the switchingforce that would be generated (or was generated) if the normal force ora switching force was generated by way of the linear motor section(s) inother regions of the transport system. For example, if the movabletransport element is driven downstream of the transition region by alinear motor section, then the normal force between this linear motorsection and the transport element in the transition region can bechanged (reduced, increased). In addition, a further normal forcecomponent can be present in the transition region, e.g. due to an addedlinear motor section, which is also changed (reduced, increased) ascompared to the normal force between the added linear motor section andthe movable transport element.

The devices for changing the normal force can be provided in particularto reduce the normal force. For example, these devices can be suitableto influence the normal force in such a way that it is lower in thetransition region, in particular, for example downstream of thetransition region.

For example, in the transition region of the switch, the air gap betweenthe two linear motor sections and a moving transport element can beenlarged, for example, larger than downstream of the transition region.

By enlarging the air gap in the switch region, the (magnetic) normalforce, which typically reduces by the power of two with the width of theair gap, reduces faster than the switching forces which typically reducelinearly therewith, so that the relationship between the switching forceand the normal force improves with an enlarging air gap.

Such an enlargement of the air gap between the two linear motor sectionsand a moving transport element can be carried out in particular in that,in the transition region of the switch, the two linear motor sectionsare offset in relation to the boundary of the transport track, i.e. donot run at the same distance from the edge of the transport track likein other regions of the switch (e.g. downstream at the end of theswitch), but are in the transition region set with a greater distance tothe respective edge of the transport track.

Alternatively or additionally, the air gap between the two linear motorsections and a moving transport element can also be enlarged in that thelinear motor sections are installed rotated in relation to the normaldirection of installation in relation to each other and to the transporttrack (or the edge of the transport track).

Alternatively or additionally, the air gap between the two linear motorsections and a movable transport element can also be enlarged in thatthe distance between the transport element and the linear motor sectionsis enlarged by a special guide curve for the transport element, i.e. theguide curve in the transition region of the switch is guided in such away that a greater distance between the linear motor sections and thetransport element arises than in other regions of the switch, e.g.downstream at the end of the switch. This can be done, for example, inthat the guide curve leads the transport element away from the edge ofthe transport track.

Additionally or alternatively, the transition region can be enlarged bya wider formation of the transition region, i.e. the two linear motorsections in the transition region are guided with a greater distance tothe guide curve than in other regions of the switch (e.g. downstream atthe end of the switch).

Alternatively or additionally, the normal force can be reduced in thatthe magnetic conductivity of the linear motor sections is reduced in thetransition region, i.e., for example, is smaller than in another regionof the switch, e.g. downstream of the transition region.

The magnetic conductivity of the linear motor sections in the transitionregion can be reduced, for example, in that (at least) the ferromagneticpart of the linear motor sections in the transition region are formed totaper, thus becoming narrower. Thereby, for example, its core, such as,an iron core, can be formed thinner in that region. This can reduce themagnetic conductivity of the linear motor sections as compared toregions where the ferromagnetic part of the linear motor sections is nottapered. The normal force in the regions of the taper can thus bereduced. Only the core of the linear motor sections in the transitionregion can then be tapered and optionally the outer boundary of thelinear motor sections can be unchanged in their diameter, oralternatively the linear motor sections themselves can also be tapered.

Alternatively or additionally, a part of the linear motor base body inthe transition region can be made of a different material than, inparticular, the linear motor base body in at least one other region, forexample, downstream at the end of the switch. The linear motor base bodyis typically made of iron. The different material typically exhibits alower magnetic conductivity (magnetic permeability), so that themagnetic conductivity can be reduced. The linear motor base body in thetransition region can there be partially or entirely made of thedifferent material.

In some embodiments, a current supply can be provided in the transitionregion and allow actuating two independently actuatable electromagnetson a transport element, each facing a linear motor section. Theactuation can be possible or be coupled independently of each other forthe two electromagnets. The current supply is typically configured insuch a way that the first electromagnet of the transport element can beswitched such that the normal force is increased on the side facing afirst linear motor section, and the second electromagnet is switchedsuch that the normal force on the side facing the second linear motorsection is reduced. A reverse connection is typically also possible, sothat the transport element can optionally be guided along the main trackor transferred into the secondary track. The change of the normal forcecan thus contribute to the transfer of the movable transport elementinto the selected track (increase the switching force).

The invention further comprises a movable transport element for atransport system. The movable transport element is typically configuredto be moved on a transport system and typically comprises, inparticular, a magnetic reaction element with which the transport elementis movable on the transport track, typically along a guide, andcontrolled by the linear motor sections.

In addition to the magnetic reaction element, the movable transportelement can also comprise two independently switchable electromagnetsand/or the magnetic reaction element can be formed by two independentlyswitchable electromagnets. These electromagnets are typically formed insuch a way that they can be actuated separately in the transition regionof the switch, e.g. with a current supply described above, so that thenormal force on the side facing one linear motor section can be reducedand on the other side be increased so that the transport element can beguided more reliably optionally along the main track or into thesecondary track of the switch.

According to the invention, devices for increasing the switching forcecan be provided for a switch in the transition region.

In particular, the linear motor sections, for example, in the transitionregion, can be formed in such a way that the magnetic field strength ofthe linear motor sections can be switched higher than, in particular,downstream of the transition region in the main track and/or thesecondary track and/or upstream. This can mean, in particular, that themagnetic field strengths of the linear motor sections for this regionthat are possible for safe operation are higher.

An increase in the field strength in the linear motor sections increasesthe interaction between the linear motor sections (stators) and themovable transport element (more precisely: the magnetic reaction elementor elements or other (passive) magnetic elements of the movabletransport element). With a higher magnetic field strength, inparticular, the resulting switching force can be increased.

In this case, the switching force can be effected in that only onelinear motor section is energized and thus exerts an attracting force inthe direction of the selected track (main or secondary track), while theother is not energized, so that the movable transport element is guidedin a direction and to the desired track. Instead of not energizing alinear motor, the latter can alternatively be energized such that itexerts a repelling force upon the movable transport element, so that therepelling effect additionally “pushes” the movable transport element inthe direction of the desired track.

Such formation of the linear motor sections allowing higher switching ofthe magnetic field strength can comprise, for example, that the numberof turns of the linear motor sections in the transition region is higherthan at least any other point of the switch or the transport system, inparticular, e.g. downstream at the end of the switch and/or upstream ofthe transition region. With a higher number of turns, the maximumpossible advance speed reduces, so that switches with an increasednumber of turns can typically be used in transport systems in which thesame advance speed as upstream on the switch need not be realized.

Alternatively or additionally, the current-carrying capacity of thelinear motor sections in the transition region can he increased, e.g. behigher than downstream and/or upstream of the transition region. Thiscan be made possible, for example, by using coils with higher coilcross-sections. With such larger coil cross-sections, the same thermalload can be obtained at a higher electric current, i.e. the thermallimits can still be observed.

Alternatively or additionally, components with higher thermal limitsallowing an increase in the electric current can be employed.

Alternatively or additionally, heat dissipation can be improved in thetransition region, e.g. be better than in a region downstream and/orupstream. Better heat dissipation can be achieved by better cooling,such as with additional cooling fins, water cooling, improved watercooling or the installation of a fan, and/or improved convection.Additional cooling can increase the current-carrying capacity becausethe thermal limits are then reached less quickly than without cooling.

Alternatively or additionally, the switch can comprise actuatable coilsin the transition region which are present in addition the coils of thelinear motor sections and are suitable for increasing the switchingforce in combination with one or more magnetically conductive passivecomponents on a movable transport element.

For example, additional coils can be comprised in the transition regionof the switch. They can be arranged, for example when visualizing aplane that passes through the two linear motor sections, perpendicularto the plane above and below (or to the right and the left of) thisplane. The coils can be arranged together with the linear motor sectionsin a plane perpendicular to the visualized plane through the linearmotor sections. If the coils have a width that differs from that of thecoils of the linear motor sections, the plane visualized typicallyrelates to the plane of the coil side facing the movable transportelement. Alternatively, they can be offset rearwardly in the directionparallel to the visualized plane through the linear motor sections inthe direction of the transport track.

A transport element according to the invention can comprise one or moremagnetically conductive passive components which are arranged in such away that they can interact together with the previously described coils,which can be present in the transition region in addition to the coilsof the linear motor sections, to increase the switching force. Inparticular, the switching force can be increased in the selecteddirection along the main track or into the secondary track by theinteraction between these coils and the magnetically conductive passivecomponents.

Passive components can be configured, for example, as part of thetransport element and be made of ferromagnetic material such as iron, orcomprise such. They typically correspond in dimensions, at least inheight, (approximately) to the dimensions of the additionally providedcoils and are typically also spatially located in this plane. Such apassive component is typically at most as wide as the magnetic reactionelement on the transport element. The height is typically based on theforce to be achieved and is typically in the range of about 5 to 10 mm.

The invention furthermore comprises a transport system for a movabletransport element which comprises at least one transport track with atleast one switch as described above. The transport system can bedesigned, in particular, for use in the beverage industry, e.g. in abeverage filling system. A transport system can optionally comprise oneor more additional switches and/or modular continuations of the mainand/or secondary track. Such a transport system typically comprises aguide curve or other mechanical components along which the movabletransport element is guided on the transport track. Such a transportsystem can comprise a transport element described above or several ofthe transport elements described above.

The devices for increasing the switching force and changing the normalforce can be used in any combination. For example, a simultaneous change(reduction) of the normal force together with an increase in theswitching force, e.g. by additional coils and/or electromagnets, canachieve an even more reliable supply of the transport element to thedesired track of the switch.

The invention also comprises a method for switching one or more of thecomponents described above in a transport system in order to transfer amovable transport element to the selected track (along the main track orinto the secondary track).

BRIEF DESCRIPTION OF THE DRAWINGS

Further embodiments shall be described below in view of the figures,where:

FIG. 1a and FIG. 1b show a prior art switch;

FIG. 2a and FIG. 2b show a switch with a larger air gap in thetransition region between the transport track and the linear motorsections;

FIG. 3a and FIG. 3b show a different switch with a larger air gap in thetransition region between the transport track and the linear motorsections;

FIG. 4a and FIG. 4b show a further switch with a larger air gap in thetransition region between the transport track and the linear motorsections;

FIG. 5a and FIG. 5b show a switch in which the linear motor base body inthe transition region is in part made of a different material;

FIG. 6a and FIG. 6b show a switch in which the linear motor base body inthe transition region is entirely made of a different material;

FIG. 7 shows a cross-section through a transport element in thetransition region of a switch;

FIG. 8 shows a cross-section through a transport element in thetransition region of a switch; and

FIG. 9 shows a cross-section through a transport element in thetransition region of a switch.

DETAILED DESCRIPTION

FIG. 1a shows such a switch 1 known from prior art. It comprises atransition region 2, a main track 3, and a secondary track 4 into whichmovable transport element T can optionally be transferred in directionof motion B (toward the switch). Such a transfer only works, of course,if the movable transport element moves in the direction of motion B onthe transport track. A correspondingly reverse direction of motion istypically also possible. However, since the choice of direction does nothave to be made in this case, this case shall not be discussed furtherhereafter.

Along the main track, linear motor sections 5 a and 5 d in thetransition region first run in parallel, in the transition region of theswitch, linear motor sections 5 a and 5 d part from each other (divergeso that they no longer run in parallel). Downstream of the transitionregion, linear motor section 5 a is guided along main track 3 and linearmotor section 5 d along secondary track 4. Linear motor sections 5 b and5 c engage at the tip of the switch, so that movable transport elementsT are guided by two linear motor sections running parallel to eachother, also downstream of the branch-off. Linear motor section 5 b thenruns parallel to linear motor section 5 a, whereas linear motor section5 c runs parallel to linear motor section 5 d, so that linear motorsections 5 a and 5 b together can accelerate a transport element onsecondary track 3 and linear motor sections 5 c and 5 d together canaccelerate a transport element T on secondary track 4.

An exemplary beginning of transition region AÜ is drawn in in FIG. 1awhere linear motor sections 5 a and 5 d begin to diverge. This beginningof the transition region can alternatively also be in another location,e.g. can be shifted further to the left in the figure, and thetransition region can comprise a region of the main track in whichlinear motor sections 5 a and 5 d run in parallel (not shown).

In other prior art embodiments, such as shown in FIG. 1 b, the transportelements are moved along main track 3 only by one linear motor section 5a, and only in transition region 2 is another linear motor section 5 dadded with which the movable transport element can optionally betransferred to secondary track 4. An exemplary beginning of transitionregion AÜ is also marked. In the transition region of a switch (in priorart as well as with the switches described below, e.g. the switches ofFIGS. 2b, 3b, 4b, 5b ) linear motor sections 5 a and 5 d in thetransition region can optionally run in parallel in one region, beforethey part to lead along the main track or the secondary track (notshown). In such a case, the transition region, as explained by way ofexample for FIG. 1 a, can also begin at a different location, e.g. beshifted further to the left in the figure, in particular, at thebeginning of the region in which the second linear motor section joins.

FIG. 2a shows an example of a switch according to the invention, inwhich the air gap in the transition region between the two linear motorsections and a moving transport element is greater than at least atanother location of the transport track, for example, downstream. Inparticular, linear motor sections 5 a″ and 5 d″ in FIG. 2a are arrangedin the transition region offset relative to the normal arrangement oflinear motor sections 5 a′, 5 d′ and 5 a″ and 5 d″ downstream of thetransition region to the edge of transport tracks R, R′, so that alarger air gap in the transition region between linear motor sections 5a″ and 5 d″ and the edges of transport tracks R, R′ and thus typicallyalso between a transport element moving (typically along a guide) in thetransition region arises.

The air gap can have its greatest value at the beginning of thetransition region, as drawn in there by way of example. The firstcontrol operation of the movable transport element is typically carriedout at this point, so that disturbances in this region are particularlydisturbing, since they can very easily lead to the transfer of themovable transport element into the wrong track. Therefore, a reductionof the normal force is particularly advantageous in this region.

FIG. 2b shows a switch for a system in which the movable transportelement in the transport system outside the switch is driven only by onelinear motor section, e.g. on the main track (in the regions outside thetransition region) by linear motor sections 5 a′ and 5 a″ and on thesecondary track by linear motor section 5 d″, However, there isaccordingly no linear motor section 5 d′ present in FIG. 2b . The airgap in the transition region between the two linear motor sections and amoving transport element can be enlarged also in such a system accordingto FIG. 2a , i.e. the distance between each one transport element andthe linear motor section in the transition region is greater than e.g.downstream at the end of the switch or downstream of the switch when themovable transport element is further guided along this linear motorsection. The further features described for FIG. 2a can likewiseoptionally be comprises by a switch as shown in FIG. 2 b.

FIG. 3a shows an alternative embodiment in which the air gap between themovable transport element and the linear motor sections in thetransition region is likewise enlarged. Here as well, the largest valuefor the air gap can be present, in particular, at the beginning of thetransition region. In the example shown, however, the linear motorsections are not arranged offset, but formed to taper, so that anenlarged air gap toward the edge of the transport tracks R, R′ thenarises and thereby also to a movable transport element on the transporttrack. Alternatively, the diameter of the linear motor sections canremain unchanged and only the core, e.g. the iron core, of the linearmotor sections can be formed to taper (not shown).

FIG. 3b shows a corresponding switch for a system in which the movabletransport element in the transport system outside the switch is drivenonly by one linear motor section. The further features and alternativesdescribed for FIG. 3a can optionally also be comprised by a switch asshown in FIG. 3 b.

FIG. 4a shows another example of a switch in which the air gap isenlarged. In the example shown, the air gap between linear motorsections 5 a and 5 d is enlarged in that the guide (presently by way ofexample in the form of guide curves FK′, FK″) is configured accordingly,i.e. leads away from the linear motor sections. Alternatively, the airgap can also be effected by enlargement of the switch region or as anarrangement of linear motor sections 5 a and 5 d further outwardly (notshown).

The enlargement of the air gap can be effected, for example, in that aunit of the guide and the motor section, in FIG. 4a for example 5 d andFK″, is moved by the desired additional distance from unit 5 a and FK′.The distance between FK′ and FK″ can, for example, correspond to theprevious unchanged guide distance in the switch (e.g. upstream ordownstream). Due to the adjusted contour of the guide edges, similar toFIG. 4a , a larger air gap between the linear motor sections and thereaction element can then arise.

FIG. 4b shows a corresponding switch like in FIG. 4a for a system inwhich the movable transport element in the transport system outside theswitch is driven only by one linear motor section. The further featuresand alternatives described for FIG. 4a can optionally also be comprisedby a switch as shown in FIG. 4 b.

FIG. 5a shows an embodiment of a switch in which a part of the linearmotor base body is made of a different material than the remainder ofthe linear motor base body, in particular in the example of the linearmotor base body shown, e.g. downstream of the transition region. In thiscase, a material with a lower magnetic conductivity than in other partsof linear motor base bodies 5 a, 5 d and linear motor base body 5 b and5 c is typically used in regions 5 a* and 5 d*. This enables reducingthe normal force in the transition region. If the replaced volume of thebase body varies along the course of the base body, the largest portionof the linear motor base body at the beginning of the transition regionis typically replaced with a different material, so that in the regionin which disturbances typically have the most influence, the normalforce is most reduced.

FIG. 5b shows a corresponding switch for a system in which the movabletransport element in the transport system outside the switch is drivenonly by one linear motor section. The further features described forFIG. 5a can optionally also be comprised by a switch as shown in FIG. 5b.

FIG. 6a shows an embodiment of switch in which the linear motor basebody in regions 5 a* and 5 d* is formed entirely from a differentmaterial, typically having lower magnetic conductivity, e.g. than thelinear motor base bodies in regions 5 a′, 5 a″, 5 d′, 5 d″. Thedifferent material is typically arranged in the transition region.

FIG. 6b shows a corresponding switch for a system in which the movabletransport element in the transport system outside the switch is drivenonly by one linear motor section. Accordingly, linear motor sectionregion 5 d′ does not exist in the switch shown. The further featuresdescribed for FIG. 6a can optionally also be comprised by a switch asshown in FIG. 6 b.

FIG. 7 shows a cross-section through a movable transport element Taccording to the invention. In the embodiment shown, the movabletransport element comprises electromagnets E on both sides that areswitchable independently. The example shows a cross-section through thetransport element and linear motor sections 5 a and 5 d, namely in thetransition region on the main track before the transport element istransferred into the secondary track or moved further along the maintrack, but while forces to guide the transport element are alreadyacting on the selected track.

Here is the situation drawn in in which the two electromagnets Eswitchable independently of each other are switched in the samedirection, so that they both in the interaction with the linear motorsexert a force toward the left. On the side of the transport element Tdrawn in the figure on the left-hand side, electromagnet E increases thenormal force, while the electromagnet on the side shown in the figure onthe right reduces the normal force. Overall, an additional force isgenerated toward the left, so that transport element T would be guidedin this direction, and accordingly can be directed onto the track on theleft (e.g. the main track or the secondary track, depending on which oneleads to the left). A power supply for electromagnets E is not drawn in,although typically present, at least in the transition region, in asystem of the invention or in a switch in which such a transport elementcan be used. The power supply can be provided, for example, by way ofbrush pick-ups above and/or below the transport track.

Schematically drawn in also by way of example are a chassis 6 with guide7 which, however, can also be formed differently than drawn. Such aguide can be present in a switch according to the invention only in thetransition region, or only at the switch, or also in other regions ofthe transport system. Also drawn in are magnetic reaction elements 8which can be formed, for example, as permanent magnets.

Electromagnets E can also be switched differently, for example, in sucha way that the normal force on the right-hand side is strengthened andweakened on the left-hand side. In further embodiments, individuallyswitchable electromagnets E instead of permanent magnets 8 can alsoassume the task of the magnetic reaction element. Non-switchingelectromagnets instead of the permanent magnets can also be used asmagnetic reaction elements 8 in other embodiments.

FIG. 8 shows a cross-section through a transport element T on atransport track. Drawn in are schematic chasses 6 (which can also beformed differently than drawn), linear motor sections 5 a and 5 d, andmagnetic conductive passive components 10 of the transport element,which are configured to act together with actuatable coils 9 in thetransition region of the switch that are present in addition to thecoils of the linear motor sections to add a respective switching forceand thus increase the switching force.

In the example shown in FIG. 8, coils 9 are switched such that theadditional switching force acts upwardly. Other switching is possible,e.g. the coils can be switched such that the additional switching forceacts in the figure downwardly (not shown). When viewing a first planethrough (transport track and) the (middle or symmetry plane of the)linear motor sections and a second and third plane perpendicular theretoand parallel to the direction of the transport track (or the directionof motion of a movable transport element on the transport track) eachthrough the side of a linear motor facing the transport track (or thepoint of the linear motor closest to the transport track), additionalcoils 9 in the example shown are by way of example each arranged (atleast with the side facing the transport track or the point closest tothe transport track) in the same plane as a linear motor section, i.e.in the second and third plane.

In FIG. 9, there is a similar arrangement as in FIG. 8, only that in theexample shown, additional coils 9 are not disposed in the same plane asthe linear motor sections, i.e. not in the second and third planediscussed with reference to FIG. 8, but in relation to the second orthird plane are on a plane parallel thereto, but further away from thetransport track than the second or third plane.

FIG. 9 shows a connection schematically where coils 9 together withcomponents 10 exert a switching force toward the left, and a switchingforce is also generated at the same time to the left by switching linearmotor sections 5 a and 5 d, since linear motor section 5 a is switchedin such a way that the normal force is increased, and linear motorsection 5 d is switched in such a way that the normal force is reduced.Other connections (presently not shown) are of course possible, e.g. togenerate a switching force in the direction of the figure towards theright.

1-11. (canceled)
 12. A switch of a transport system for a movabletransport element, comprising: a main track; a secondary track; and atransition region, the transition region comprising: a section of themain track, the section of the main track comprising a first linearmotor section, the first linear motor section configured to move themovable transport element along the main track; and a section of thesecondary track branching off from the main track, the section of thesecondary track comprising a second linear motor section, the secondlinear motor section configured to move the movable transport elementalong the secondary track, wherein the first and second linear motorsections are configured to generate switching forces to guide themovable transport element through the transition region onto the maintrack or to switch the movable transport element to the secondary track,and wherein the switching force generated by the first linear motorsection differs from the switching force generated by the second linearmotor section.
 13. The switch of claim 1, wherein switching forcesgenerated by the first linear motor section and second linear motorsection correspond to strengths of magnetic fields produced by the firstlinear motor section and the second linear motor section.
 14. The switchof claim 1, wherein: the movable transport element comprises passivemagnetic elements, wherein the first linear motor section compriseswound stators having a greater number of turns than stators outside ofthe transition region, and wherein the second linear motor sectioncomprises wound stators having a greater number of turns than statorsoutside of the transition region.
 15. The switch of claim 1, wherein thefirst linear motor section is configured to carry a larger current thanlinear motor sections outside of the transition region, and wherein thesecond linear motor section is configured to carry a larger current thanlinear motor sections outside of the transition region.
 16. The switchof claim 1, wherein in the transition region at least one of coolingfins, water cooling, or a cooling fan is provided.
 17. The switch ofclaim 1, wherein the first linear motor section comprises a first statorwith a first set of coils, wherein the second linear motor sectioncomprises a second stator with a second set of coils, and furthercomprising actuatable coils in the transition region, the actuatablecoils configured to increase switching forces generated by the firstlinear motor section and the second linear motor section.
 18. The switchof claim 17, wherein the actuatable coils, first linear motor sectionand second linear motor section are coplanar.
 19. The switch of claim17, wherein the actuatable coils are disposed in a separate plane fromat least one of the first linear motor section or second linear motorsection.
 20. A movable transport element for a transport system,comprising: a chassis; one or more magnetic reaction elements; and oneor more magnetically conductive passive components, wherein themagnetically conductive passive components are configured to interactwith actuatable coils of linear motor sections in a transition region toincrease a switching force exerted upon the transport element.
 21. Atransport system for a movable transport element, comprising: atransport track; and a switch connected to the transport track, theswitch comprising: a main track; a secondary track; and a transitionregion, the transition region comprising: a section of the main track,the section of the main track comprising a first linear motor section,the first linear motor section configured to move the movable transportelement along the main track; and a section of the secondary trackbranching off from the main track, the section of the secondary trackcomprising a second linear motor section, the second linear motorsection configured to move the movable transport element along thesecondary track, wherein the first and second linear motor sections areconfigured to generate switching forces to guide the movable transportelement through the transition region onto the main track or to switchthe movable transport element to the secondary track, and wherein theswitching force generated by the first linear motor section differs fromthe switching force generated by the second linear motor section. 22.The transport system of claim 21, further comprising: a first movabletransport element, the first movable transport element comprising: achassis; one or more magnetic reaction elements; and one or moremagnetically conductive passive components, wherein the magneticallyconductive passive components are configured to interact with actuatablecoils of linear motor sections in the transition region to increase aswitching force exerted upon the first movable transport element.